One of Donald Trump’s signature campaign promises was to build a wall between the United States and Mexico. Trump pitched this as a bold step in his fight against illegal immigration. This plan was widely criticized as being xenophobic, expensive, and ineffective, but Trump has maintained the necessity of the wall. Unfortunately for him, some within his own political party are starting to speak out against the measure.

During the campaign, many Republicans were wary of speaking out against the wall for fear of alienating Trump’s base. However, now that the election is over, Republicans are beginning to jump ship. A large part of this is due to the cost of the wall which is estimated to be about $22 billion.

Reps. Will Hurd (R-Texas) and Martha McSally (R-Ariz.) both represent border districts and issued a statement asking the president to address their concerns regarding the price of the wall.

‘We recognize the need for robust border security and infrastructure to ensure public safety and increase cross border commerce. We also have an obligation to be good stewards of taxpayer dollars.’

It isn’t just the material costs that have some Republicans concerned; it is also the strain it will put on the relationship between the U.S. and Mexico. In a Senate Homeland Security Committee hearing, Sen. John McCain (R-Ariz.) warned that talk of a border wall was stirring up anti-American sentiment in Mexico.

‘There is a lot of anti-American sentiment in Mexico. If the election were tomorrow in Mexico, you’d probably have a left-wing, anti-American president in Mexico. That can’t be good for America.’

Homeland Security Secretary John Kelly agreed that such an election “would not be good for America, or for Mexico.”

On the other side of the aisle, Democrats remain united in their opposition to Trump’s wall. Rep. Joseph Crowley (N.Y.) pointed out that the wall is a major expense that will do nothing in terms of driving economic growth.

‘It’s anywhere between $26 billion and $40 billion to build it, you can’t drive on it, you can’t use it for anything, it doesn’t do anything to drive economic growth and jobs in America beyond the building of a wall itself, and it probably wouldn’t be built using union jobs to begin with.’

Right now, it is unclear just how far Trump is willing to push the issue of a border wall. It was a signature promise of his campaign, but, given his recent attacks on members of his own party, his advisers, especially Jared Kushner, may be pressuring Trump to let the matter drop if isn’t able to generate enough support within the GOP.

Rather or not Trump is able to garner enough Republican support to begin construction of the wall remains to be seen. Despite his reputation as a deal maker, his push for a repeal of Obamacare failed thanks to opposition from the hardline Freedom Caucus. This defeat prompted Trump to sent out a tweet calling for the defeat of both the Freedom Caucus and Democrats.